It is known from to transmit optical rays via optical fibers and catheter systems into the interior of a body, wherein the optical fibers are each provided with suitable scatter bodies.
Furthermore, a working shaft is known from DE-C-35 12 018, wherein a fluid is used for cooling and as the waveguide.
However, a number of grave problems arise when it is attempted to also use such systems in connection with endoscopic surgery or interventionally. In particular, impermissible heating occurs in the immediate vicinity of the distal end of the working shaft, which can constitute impermissible impairments.
Furthermore, the direction of the beam cannot be controlled and thus the effect cannot be visually observed simultaneously nor generally modified.
It is the object of the invention to provide the opportunity in connection with a working shaft of the type mentioned at the outset to apply a light beam to the interior of a body in a particularly simple manner in such a way that heating in the immediate area does not exceed impermissible values.
It should be possible in particular to affect the intensity and direction of thermal treatments over a wide range from outside of the body.